[INFO] fetching crate overflower 0.4.6...
[INFO] testing overflower-0.4.6 against beta-2021-08-01 for beta-1.55-1
[INFO] extracting crate overflower 0.4.6 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate overflower 0.4.6 on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate overflower 0.4.6
[INFO] finished tweaking crates.io crate overflower 0.4.6
[INFO] tweaked toml for crates.io crate overflower 0.4.6 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded overflower_support v0.1.5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 391b83f164fa5a3cf794a440892620417e9552bd90486a5bd51ec450a1a0a177
[INFO] running `Command { std: "docker" "start" "-a" "391b83f164fa5a3cf794a440892620417e9552bd90486a5bd51ec450a1a0a177", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "391b83f164fa5a3cf794a440892620417e9552bd90486a5bd51ec450a1a0a177", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "391b83f164fa5a3cf794a440892620417e9552bd90486a5bd51ec450a1a0a177", kill_on_drop: false }`
[INFO] [stdout] 391b83f164fa5a3cf794a440892620417e9552bd90486a5bd51ec450a1a0a177
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5f3dd0d678c9f5aba1738a3a0455568b898cbd4f5ac2324d4af8bab214368c39
[INFO] running `Command { std: "docker" "start" "-a" "5f3dd0d678c9f5aba1738a3a0455568b898cbd4f5ac2324d4af8bab214368c39", kill_on_drop: false }`
[INFO] [stderr]    Compiling overflower_support v0.1.5
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/overflower_support-0.1.5/src/lib.rs:14:1
[INFO] [stdout]    |
[INFO] [stdout] 14 | #![feature(specialization)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `overflower_support` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "5f3dd0d678c9f5aba1738a3a0455568b898cbd4f5ac2324d4af8bab214368c39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5f3dd0d678c9f5aba1738a3a0455568b898cbd4f5ac2324d4af8bab214368c39", kill_on_drop: false }`
[INFO] [stdout] 5f3dd0d678c9f5aba1738a3a0455568b898cbd4f5ac2324d4af8bab214368c39
